I'm in the same boat.
After some considerable amount of time sat on my fat backside I have no started to do abit of phys, but instead of using the gym I strap my bike onto a turbo trainer and do my spinning from a Youtube video. It's a fat burner and for 20 min's, pretty good and in the comfort of your own home.
Btw it is working. All it takes is abit of motivation, which is the hardest part I find.